The cephalosporin compounds are useful compounds having antibacterial activities. Active studies have been made on their synthesis, and many compounds have already been produced. Some of them now occupy clinically important positions as antibiotics having a broad antibacterial spectrum.
In general, most of the broad-spectrum cephalosporin antibiotics now in use in clinical situations have hardly any antibacterial activity against Pseudomonas bacteria, while those having antibacterial activities against Pseudomonas bacteria are slightly effective on Gram-positive bacteria, Gram-negative bacteria, and the like. That is, there has not yet been discovered any broad-spectrum cephalosporin antibiotic having antibacterial activities against all of these bacteria. Accordingly, any of the broad-spectrum cephalosporin antibiotics, for example, cefzonam, flomoxef and ceftazidime, are either ineffective on Pseudomonas bacteria or weak in antibacterial activities on other bacteria even when they are effective on Pseudomonas bacteria.
Accordingly, an object of the present invention is to provide cephalosporin antibiotics having a broad antibacterial spectrum and noticeable antibacterial activity against Gram-positive bacteria, Gram-negative bacteria, etc. as well as against Pseudomonas bacteria.
Another object of the present invention is to provide production methods for making said cephalosporin antibiotics.
A further object of the present invention is to provide intermediate compounds for the production of said cephalosporin antibiotics.
A further object of the present invention is to provide pharmaceutical compositions containing said cephalosporin antibiotics.
A further object of the present invention is to provide methods for the treatment of bacterial infectious diseases by administration of said cephalosporin antibiotics.